1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Soloha48 [4]
4 years ago
8

What is the sign of enthalpy change for (a), an endothermic reaction? (b). an exothermic reaction?

Chemistry
1 answer:
fenix001 [56]4 years ago
8 0

Answer:

The answer is: (a) positive; (b) negative.

Explanation:

The change in enthalpy (ΔH) of a reaction is the amount of energy absorbed or released during a chemical reaction carried out at constant pressure.

a) In an endothermic chemical reaction, heat energy is absorbed by the system from the surrounding. Therefore, the sign of enthalpy change for an endothermic process is positive, ΔH= positive.

b) In an exothermic chemical reaction, heat energy is released by the system into the surrounding. Therefore, the sign of enthalpy change for an exothermic process is negative, ΔH= negative.

You might be interested in
Is this a redox reaction? give evidence (many points plz answer)<br> 2Mg + CO2 → 2MgO + C
Aleonysh [2.5K]

Answer:

\boxed{yeah}

Explanation:

CO_2 \:  is \: reduced \: to→C \: by \:  2M_g \: (the \: reducing \: agent): while \\ 2M_g \: is \: oxydized \: to→2M_gO \: by \:  CO_2 \: (the \: oxydizing \: agent)

6 0
3 years ago
Sodium combines with water to produce sodium hydroxide and hydrogen gas. Which word equation represents this violent reaction?
Natalka [10]

Answer: sodium + water → sodium hydroxide + hydrogen

Explanation:

1) The first part of the statment "sodium combines with water" means that these two pure substances are the reactants.

Sodium is an alkali metal (group 1: Li, Na, K, Rb, Cs, Fr).

A typical chemical property of the alkali metal elments is that they react violently with water fo form the corresponding hydroxide and hydrogen gas.

2) The next two words, "to produce ". indicates, precisely, that what follow is the product of the reaction. In the chemical reaction it is indicated by the arrow →

3) Finally, you are told the products of the reaction: sodium hydroxide and hydrogen gas.

4) The word equation then follows the order reactants → products, which in this case is the sodium + water → sodium hydroxide + hydrogen

5) Using chemical symbols and conventions, that is:

Na(s) + H₂O (l) → NaOH(aq) + H₂(g).

5 0
3 years ago
Read 2 more answers
C8H10N4O2 is the chemical formula for caffeine. List the 3 remaining elements in caffeine and how many atoms of that element are
velikii [3]
No idea , sorry. maybe it is.....actually i dont know, sooo sorry
7 0
3 years ago
Methane reacts with chlorine to produce methyl chloride and hydrogen chloride. Once formed, the methyl chloride may undergo furt
balandron [24]
Your gonna half to space this out in order for me to answer if you don’t mind. I’ll answer in the comments
5 0
3 years ago
How many points should be plotted when creating a scatterplot from the table of values below?
Fed [463]

Answer:

I think the correct answer would be 6.

Hope that was helpful.Thank you!!!:)

8 0
4 years ago
Other questions:
  • If two fatty acids, glycerol, and a phosphate group undergo a dehydration reaction, what molecule forms
    15·1 answer
  • Which does not damage geothermal electricity-generating systems?
    8·2 answers
  • A stream of negatively charged particles is called:
    7·1 answer
  • The atomic masses of 151eu and 153eu are 150.919860 and 152.921243 amu, respectively. The average atomic mass of europium is 151
    10·1 answer
  • How many grams of lead(II) sulfate (303 g/mol) are needed to react with sodium chromate (162 g/mol) in order to produce 0.162 kg
    6·1 answer
  • The use of nuclear power in place of coal, oil, and natural gas greatly reduces emissions of carbon dioxide and other greenhouse
    10·2 answers
  • How many atoms does 6.022x10^23 formula units if water have
    5·1 answer
  • 8) Cuándo se realizan trabajos de investigación siempre se trata de expresar los resultados de forma gráfica porque permite un a
    11·1 answer
  • What is the common name of the compound CaoCl2?​
    8·1 answer
  • Please help (20 points)
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!